The invention is directed to a method for the assembly of picture screen devices, and in particular to a method using a clamp connection and a mount for a picture tube.
At present, many time-wasting, small, individual steps, part of which are exclusively manual tasks, are carried out on a carrier element in the assembly of a picture tube and its corresponding viewing window. Among other things, the demand that the inside edge of the viewing window bezel lie flush against the spherical picture screen surface of the picture tube on all sides presents great difficulties.
In order to meet this demand, one known assembly method employs spacer pins which are first screwed into a picture tube carrying frame which is then placed in an assembly jig. The bezel is then pressed against the front of the picture tube, which is held by the spacer pins, until claws which are attached to the sides of the diaphragm engage and retain the carrying frame with the picture tube in between. Due to loose manufacturing tolerances of the glass member of the picture tube, however, the claws either do not properly engage the pins of the carrier or the bezel is loosely seated around the picture tube. Re-adjustment must therefore be undertaken with the spacer pins. To accomplish this the bezel must be removed again so that all screws and nuts fixing the picture tube and the spacer pins can be loosened. After the spacer pins have been appropriately adjusted and all nuts have been tightened again, the bezel is put back in place and a check of the spacing between the inside edge of the bezel and the spherical picture screen surface of the picture tube is once again carried out. This time-consuming adjusting procedure may have to be carried out repeatedly until proper engagement is obtained. Work facilitating accessories such as, for example, assembling jigs are usually employed for individual work steps and industrial robots are also utilized for various activities during assembly. As a consequence of the unfavorable structure of both the holding device and the picture tube, however, the complete assembly of picture screen devices by an industrial robot is difficult, especially when the demand that the inside edge of the viewing window bezel press flush against the picture screen surface on all sides is taken into consideration.